1. Field of the Invention
The present invention relates to a treatment for increasing the choroidal blood flow using 13,14-dihydro-15-keto-20-ethyl-prostaglandin Fs, salts or lower alkyl esters thereof.
2. Background Information
The compounds used in the present invention, i.e. 13,14-dihydro-15-keto-20-ethyl-prostaglandin Fs, salts or lower alkyl esters thereof are known compounds and described in EP-A-289349 (particularly in Examples 7, 11, 12, 13, 14 and 24) and EP-A-308135 (particularly in Example 8). In the former publication, the compounds are described as having a blood pressure increasing activity and in the latter publication, the compounds are described as having an ocular hypotensive activity. Nothing has been reported, however, about an activity of the above compounds on the choroidal blood flow. As a result of a study about the biological activity of 13,14-dihydro-15-keto-20-ethyl-prostaglandin Fs, salts or lower alkyl esters thereof, it has now been discovered that these compounds have an activity of increasing choroidal blood flow.